The administrator of the underground forum wrote on Friday that it "only took 74 days to confirm the breach," linking to a story on the BBC.
FriendFinder Networks wrote that it had hired FireEye's forensics unit, Mandiant, to investigate along with Holland and Knight, a law firm, and a public relations company specializing in cybersecurity.
"We cannot speculate further about this issue, but rest assured, we pledge to take the appropriate steps needed to protect our customers if they are affected," it said. The company could not be reached for further comment.
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